Chore Monster is a website and iPhone app that encourages your kid to do chores around the house. Parents set up a list of chores for their kids to do, such as making the bed, setting and clearing the table, taking care of pets, taking out the trash, etc. Each chore gets assigned a certain number of points. These points can be redeemed for rewards, such as cash, screen time, iTunes gift cards, and so on. They also earn random pet monsters as they complete chores.
Each child gets an account with a username and password, and they can keep track of their chore score on the Chore Monster iPhone app. When they accumulate enough points, they can redeem them for one of their rewards. I just registered and downloaded the app, so I don't know if this is going to work or not. I hope so!